Common Watersnake
Nerodia sipedon • Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Eastern and central North America, ranging from southern Canada down through the eastern United States to the Gulf Coast and as far west as Kansas and Nebraska.
Look up Common Watersnake in the Snake Encyclopedia →Family
Order: Squamata, Suborder: Serpentes, Family: Colubridae, Subfamily: Natricinae, Genus: Nerodia, Species: Nerodia sipedon
Conservation
IUCN Red List status is Least Concern. Populations are generally stable, though local threats include habitat degradation, pollution of waterways, and intentional killing by humans due to misidentification.
Physical Description
Stout-bodied snake with heavily keeled scales giving it a rough texture. The dorsal pattern features dark brown or reddish-brown crossbands on the neck region that transition to alternating dark blotches on the back and sides over a lighter tan, gray, or brownish ground color. The head is relatively distinct from the neck with dark markings.
Size & Dimensions
Estimated specimen length is approximately 30 to 42 inches. Typical adult size ranges from 24 to 42 inches (60 to 106 cm), with exceptional specimens reaching up to 55 inches (140 cm). Females are generally larger than males.
Habitat
Found predominantly in or near freshwater environments such as streams, rivers, lakes, ponds, swamps, marshes, and temporary pools. Usually stays close to the water's edge, utilizing basking sites on logs, rocks, or overhanging branches.
Diet & Feeding
Diet consists primarily of fish and amphibians (such as frogs and salamanders), but may occasionally consume small mammals, birds, or crayfish. They are active foragers both in and out of the water, capturing prey and swallowing it live without constriction.
Reproduction
Viviparous (live-bearing), giving birth to litters typically ranging from 8 to 30+ young in late summer (August to October). Mating generally occurs in the spring after emerging from brumation.
Look-alikes
Frequently confused with venomous pit vipers such as the Cottonmouth (Agkistrodon piscivorus) or Copperhead (Agkistrodon contortrix) due to a thick body and similar color patterns. Distinguished from cottonmouths by round pupils, lack of facial pits, distinct labial bars, and a more slender head shape.
Conservation Status
IUCN Red List status is Least Concern. Populations are generally stable, though local threats include habitat degradation, pollution of waterways, and intentional killing by humans due to misidentification.
Cultural Significance
Plays an important ecological role in aquatic and wetland food webs by regulating populations of fish and amphibians. Often suffers from negative human perceptions and misidentification with dangerous species.
Notable Features
Possesses strongly keeled scales and a specialized semi-aquatic lifestyle. When cornered or handled, they are known to emit a foul-smelling musk from cloacal glands, flatten their bodies to appear larger, and strike readily.